Defects in PRODH are the cause of type I hyperprolinaemia (MIM:239500). It is a disorder characterized by elevated serum proline levels. May be involved in the psychiatric and behavioral phenotypes associated in the 22q11 velocardiofacial syndrome.

[PMID 18408230] Structural cerebral variations as useful endophenotypes in schizophrenia: do they help construct "extended endophenotypes"?